1. Field of the Invention
The present invention relates to an electrical connector, and particularly to an electrical connector which has two shieldings coated with different material for promoting the efficiency of the shielding effect.
2. The Prior Art
Advanced electrical connectors, particularly high frequency electrical connectors, are covered with a corresponding shielding for suppression of noise during signal transmission. The shielding is further installed with a positioning device for effectively positioning the connector onto a printed circuit board to have a stable soldering effect during a wave soldering procedure. Some related patents are U.S. Pat. Nos. D345,343, D344,492, D345,140 5,017,156 and Taiwan Patent Nos. 81,110,335 81,217,896 81,300,211 82,101,300 83,310,726 84,104,611. However, the shielding devices as disclosed in the above patents are made by stamping and bending from a single body which, for subsequent wave soldering, must be coated with nickel (Ni) and tin (Sn) on the surface thereof. However, the Sn-coated surface, due to its softness, is apt to be partially scratched or peeled off during assembly, therefore, the outer appearance thereof is affected. The other drawback is that the positioning of the above connectors on the mother board is not secure enough thus causing unstable displacement during the wave soldering procedure which adversely affects the electrical connection of the contacts with the mother board. Therefore, an improved high frequency electrical connector which can overcome the drawbacks of conventional electrical connectors is required.